Office intelligent lighting system based on the natural lighting and the ZigBee wireless network

A comfortable and healthy lighting environment cannot only make people comfortable and improve work efficiency, but also avoid visual fatigue caused by the discomfortable lighting environment. In order to solve these problems, this paper proposes an intelligent lighting system that takes natural lighting and the occupancy situation as input and dimming factor K (0<K<1) as output. The linear function between illuminance of the working surface and natural lighting, the occupancy situation, illuminance components of adjacent luminaires, and dimming factor K is obtained through the control algorithm. The simplex method is one of the most commonly used and effective algorithms for solving linear programming problems, so the optimal dimming factor K of each luminaire is obtained. The intelligent lighting system uses the ZigBee tree network structure to transmit the dimming factor to each lamp, making the office lighting environment reach the target value. Opnet is used as a network simulation software to verify system information, such as delay, throughput, and load. The results show that the network transmission delay is only 0.011 s, and the load and throughput are both above 3.0×10⁴bits/s. As an optical software, DIAlux simulates the lighting environment under the control system in two modes: day and night. The results show that the illuminance of the occupied working surface under the system reaches 500l×, and the illuminance of the unoccupied working surface reaches 300l×. The uniformity of illuminance is greater than 0.7. In the day mode, the uniformity of illuminance is improved compared to without any control system. Finally, the energy-saving efficiency of the control system reached 34% and 25% during the day and night, respectively.